Characters in the Diablo universe is what makes it interesting. From the Diablo games' different classes to NPCs and regular inhabitants of Sanctuary introduced from books and comics. They are all what makes the universe of the games.

Please note that in most cases, the term "character" is slang for "player character" or "character class". It refers to the class you play in a given game. If a player says: "My Barbarian character", they really mean: "My character of the Barbarian class", it's just easier to say the first one.

Then starts Diablo II, and a new band of adventuring heroes follows the Wanderer's footsteps to stop him freeing his brothers (and complete the transformation into Diablo). The group of heroes are generally counted as a solid group, with one or more of each class following through the story line. These are semi-anonymous, and as is previously stated, the only Diablo II character to appear in Diablo III is the Barbarian.

There are hundreds of characters in the Diablo universe, but the most important ones are of course Diablo, Mephisto, Baal and Tyrael, who have played the largest roles in the games up until the third one, where we will see if things might be put on end. The heroes of the games have in the lore been anonymous, so even if we associate strongly with them, they remain unnamed.

NPCs are characters played by the computer in the Diablo games. They usually have proper names, and some sort of background. Most of the important characters in the universe has or will be represented as an NPC in a Diablo game.